Electronic components of various type require heat transfer systems in order to remove excess heat generated in the operation thereof. Excess heat can reduce performance of the electronic components, and, in some cases, can lead to damage or shut down of the electronic components. A common electronic component in need of heat transfer systems is an integrated circuit, such as a microprocessor, which typically generates significant amounts of excess thermal energy.
One mechanism for transferring excess heat from, for example, integrated circuits, utilizes a thermal interface material (TIM) placed between the integrated circuit and a thermal diffusion structure, which typically has high surface area for efficient heat transfer to a cooling medium such as air. The thermal interface material is typically one that is highly thermally conductive, and is preferably “conformable” so as to conform to the uneven surfaces of the electronic component and the thermal diffusion structure without substantial gaps, which create barriers to heat transfer. The thermal interface material may posses a relatively low bulk modulus value in order to provide the conformability characteristic described above, and to therefore most efficiently transfer thermal energy away from the operating electronic component. Some thermal interface materials are “phase-changing”, in that their native viscosities decrease in elevated temperature environments, such as in proximity to an operating electronic component. In most installations, however, thermal interface materials have relatively low modulus values even at room temperature. Typical TIM modulus values at 20° C. may be less than about 70 Shore 00, and may be between about 5-70 Shore 00. This modulus range often results in a relatively “tacky” surface characteristic of the TIM.
Conventional thermal interface materials include various types of pastes, gels, and metals, and may be executed in a variety of formats. An increasingly popular format for thermal interface materials is a “pad” or a defined body with substantially defined surfaces and dimensions. Such thermal interface pads have proven useful and efficient in packaging and installation, and particularly in connection with “pick and place” installation operations.
The attachment of TIMs to electronic devices typically involves a number of process steps. The increasing prevalence of “pick and place” installation systems for thermal interface pads has reduced the number of process steps required in the attachment of thermal interface materials to electronic components. However, pick and place systems are most effective when used in connection with rigid, non-tacky structures, and efforts to implement the installation of relatively low-modulus TIM with pick and place equipment has therefore been challenging. A primary problem encountered in this scenario is the TIM becoming wholly or partially adhered to the pick and place equipment and/or the TIM packaging. Such adherence can damage the TIM, and can also require installation equipment shut down for cleaning.
In some cases, releasable surface liners have been employed in relatively low-modulus thermal interface pads so that the pad may be readily disengaged from the installation equipment. Addition of release liners, however, increases the cost of the thermal interface pads, and requires a further process step to remove the release liner prior to attachment of a thermal diffusion structure to the electronic apparatus. Other efforts have focused on an integrated, relatively highly cross-linked integrated surface layer for interfacing with the pick and place installation equipment. Neither of such solutions, however, address the tackiness of the thermal interface pad where the pad is stored in packaging. Consequently, delivery of thermal interface pads to installation facilities through conventional packaging has resulted in unsatisfactory rates of TIM damage due to undesired adherence of the thermal interface pad to the packaging. The tackiness of the relatively low modulus thermal interface pads adheres to conventional packaging systems, and inhibits efficient and damage-free removal of the thermal interface pads therefrom.
Therefore it is an object of the present invention to provide packaging which facilitates delivery and removal of a tacky product, such as a thermal interface pad, by thermal interface installation equipment.
It is another object of the present invention to provide packaging that is compatible with conventional tape and reel packaging systems, which packaging facilitates efficient and non-destructive removal of tacky products from respective receptacles in the packaging.
It is a still further object of the present invention to provide methods for facilitating installation of tacky products, such as thermal interface pads, to heat-generating components.